Act to make provision for the compilation of a Register of the Population of the Union; for the issue of Identity Cards to persons whose names are included in the Register; and for matters incidental thereto.

The Population Registration Act of 1950 required that each inhabitant of South Africa be classified and registered in accordance with his or her racial characteristics as part of the system of apartheid.[1][2][3]

Race classification certificate issued in terms of the Population Registration Act

Explanation of South African identity numbers in an identity document during apartheid in terms of official White, Coloured and Indian population subgroups

Social rights, political rights, educational opportunities, and economic status were largely determined by the group to which an individual belonged. There were three basic racial classifications under the law: Black, White and Coloured (mixed). Indians (that is, South Asians from the former British India, and their descendants) were later added as a separate classification as they were seen as having "no historical right to the country".

An Office for Race Classification was set up to overview the classification process. Classification into groups was carried out using criteria such as outer appearance, general acceptance and social standing. For example, it defined a "white person" as one who "in appearance is obviously a white person who is generally not accepted as a coloured person; or is generally accepted as a white person and is not in appearance obviously a white person." Because some aspects of the profile were of a social nature,[2] reclassification was not uncommon, and a board was established to conduct that process. For example, the following criteria were used for separating the coloureds from the whites:[2]

Characteristics of the person's head hair

Characteristics of the person's other hair

Skin colour

Facial features

Home language and especially the knowledge of Afrikaans

Area where the person lives, the person's friends and acquaintances

Employment

Socioeconomic status

Eating and drinking habits

This law worked in tandem with other laws passed as part of the apartheid system. Under the Prohibition of Mixed Marriages Act of 1949, it was illegal for a white person to marry a person of another race. With the enactment of the Immorality Amendment Act of 1950, it also became a crime for a white person and a person of another race to have sexual intercourse.

^Lehohla, Pali (5 May 2005). "Debate over race and censuses not peculiar to SA". Business Report. Retrieved 25 August 2013. Others pointed out that the repeal of the Population Registration Act in 1991 removed any legal basis for specifying 'race'. The Identification Act of 1997 makes no mention of race. On the other hand, the Employment Equity Act speaks of 'designated groups' being 'black people, women and people with disabilities'. The Act defines 'black' as referring to 'Africans, coloureds and Indians'. Apartheid and the racial identification which underpinned it explicitly linked race with differential access to resources and power. If the post-apartheid order was committed to remedying this, race would have to be included in surveys and censuses, so that progress in eradicating the consequences of apartheid could be measured and monitored. This was the reasoning that led to a 'self-identifying' question about 'race' or 'population group' in both the 1996 and 2001 population censuses, and in Statistics SA's household survey programme.